... lengths are compensated for by high stride frequencies, ranging beyond 40 Hz. This is mainly achieved by a combination of short stance phases (down to 7 ms) and fast leg swing movements (up to 1400 mm s −1 ). The legs of one tripod group exhibit almost perfect synchrony in the timings of their lift-offs...

.... The exotendon applies assistive forces to the swinging legs, increasing the energy optimal stride frequency. Runners then adopt this frequency, taking faster and shorter strides, and reduce the joint mechanical work to redirect their center of mass. Our study shows how a simple spring improves running economy...

...Samuel Rubin; Maria Ho-Yan Young; Jonathan C. Wright; Dwight L. Whitaker; Anna N. Ahn ABSTRACT The Southern California endemic mite Paratarsotomus macropalpis was filmed in the field on a concrete substrate and in the lab to analyze stride frequency, gait and running speed under different...

...Tim W. Dorn; Anthony G. Schache; Marcus G. Pandy SUMMARY Humans run faster by increasing a combination of stride length and stride frequency. In slow and medium-paced running, stride length is increased by exerting larger support forces during ground contact, whereas in fast running and sprinting...

... muscles of insects (550 Hz) and toadfish (200 Hz) far exceed the contraction frequencies observed in weight-bearing locomotory muscles, which have maximum documented frequencies below 15–30 Hz. Laws of scaling, however, predict that smaller arthropods may employ stride frequencies exceeding this range...

... incline information from all areas of the track. Measurements were made from six horses over a speed range of 9 to 13 m s –1 . Foot-fall timings were used to calculate variables,which included stance duration, protraction duration, stride frequency and duty factor. The relationship between track incline...

.... * Author for correspondence (e-mail: [email protected] ) 8 11 2005 © The Company of Biologists Limited 2006 2006 design in nature animal locomotion optimality theory optimal speed maximum range speed optimal frequency stride frequency wing beat frequency Strouhal number force...

...Duncan J. Irschick; Bieke Vanhooydonck; Anthony Herrel; Anemone Andronescu SUMMARY Stride length, stride frequency and power output are all factors influencing locomotor performance. Here, we first test whether mass-specific power output limits climbing performance in two species of geckos...

... seems to adapt to muscle use, and its stiffness seems to be`tuned' to the frequency of normal muscle use. * e-mail: [email protected] 13 5 2002 © The Company of Biologists Limited 2002 2002 elastic recoil strain energy eccentric hopping stride frequency titin...

... to observe nocturnally active ghost crabs in the field for three-dimensional motion analysis ( N =27) and focal animal sampling ( N =24). Instantaneous movement velocity, movement duration, pause duration and stride frequency were determined from video tapes. Voluntarily active crabs moved at a mean...

.... At low temperatures (15°C and 22°C), stride frequency during burst running is nearly identical to the optimal cycling frequency for in vitro power output, suggesting that maximum power output may limit hindlimb cycle frequency in vivo . However, at higher temperatures (35°C and 42°C), the optimal cycling...

.... The smaller animals meet the demands of increasing speed by increasing stride length rather than stride frequency, as would be expected in a smaller species. Our results show that juvenile potoroos diverge significantly from models based only on adult animals in incremental changes in stride frequency, length...

... the freely chosen stride frequency during walking. A mathematical model that estimates the two components of the mechanical work is proposed. The model, according to the criterion of work rate minimization (both positive and positive plus negative), is able to predict the natural stride frequency...